Yes, you should be able to run Archon with your dps, at MP0-1 for maximum efficiency, I would say. You might need a Life Steal weapon but you can try with just the Blood Magic run on Magic Weapon and see how it goes, since you can probably kill elites very fast at MP0 or 1.

Have followed this wonderful guide to get geared up and have a couple of questions:

1 - What MP level do you think is realistic with my gear?
2 - Upgrades are getting expensive now - I guess Vile Ward, a Echoing with LS and Socket and a new ring are primary upgrades? Any other suggestions?
3 - This spec doesn't feel great for solo uberbosses - any suggestions for an optimal spec/MP level for these?

Thanks

:edit: Replaced my EF with one with no LS but with a socket, switching in a 2h with 6% LS and 1200 LoH with socket for hard RD packs.

1) In terms of XP and loot efficiency, I'd say MP1-2 would be optimal. You can probably run MP3 with the Archon build, but I don't see it being as efficient since mobs have like 50% more health than MP2.

2) In my experience, Echoing fury is probably overpriced for wizards because we don't get as much out of the +0.2x attacks per second as dual wielding classes. My guess is you'd get more dps out of a 1k dps sword, wand, or dagger with a socket (and life steal).

3) I really suggest a CM melee spec for soloing uber bosses. It also works great in groups at high MP level or for high MP key farming. It's what I did, though i've only solod the bosses once. Keeping a few dps pieces like your chest, shoulders, and 2pc zuni, you can probably slap together a basic set with about 60-80k+ dps capable of soloing MP4-5 for a few million. The APoC is the tricky part, but you only need 2 pieces of gear with APoC. I use helm (storm crow) and OH (triumvirate). You'd likely want to grab some bracers with resist, 140+int, 4.5% crit, and maybe armor and/or vit as well as a necklace with 8+% crit (maybe one with good defensive stats like armor and resist all, should be able to fine one for 1 mil or less). I'd recommend some Blackthorn set pants, which you can get for pretty cheap, possibly with Armor on them for a tiny bit extra. They have high EHP and a little LoH.

Overall for soloing uber bosses I'd recommend around 40% crit, 3500-4k armor, 500+resists, 16+ APoC, 30-40k hp+ as a start with CM/WW spec with full defensive stats, though at MP4-5 with those stats you can probably use pinpoint barrier over prismatic armor. One of the limiting factors in soloing the bosses is the enrage timers, which may or may not be an issue except mainly for Siegebreaker since he and Kuele are quite tough to solo, compared to the other two.

Side Note: I never really considered swapping to a high LS 2h for RD packs. I might try doing that since I have the most problems with them, though it's annoying having Magic Weapon fall off when I swap weapons or OH, but it probably won't affect my farming all that much.

3 - This spec doesn't feel great for solo uberbosses - any suggestions for an optimal spec/MP level for these?

Loroese already answered all your gear questions, I have nothing to add but one small thing: there is absolutely no reason to solo uber bosses. If you like a challenge - sure, go for it. But you will always find a group of people to help you, because for them it's a free chance for organs and you might get an invite back if they have machines and are looking for a CMWW tank mage. It's a win-win situation. If you decide to try the bosses solo you face the possibility of failing and wasting machines. Oh, and another thing: if you have a disconnect, the the portal is gone; in a group the portal stays open and you can re-join (the group has to abort the uber kill attempt though because you can't join an ongoing fight).

Side Note: I never really considered swapping to a high LS 2h for RD packs. I might try doing that since I have the most problems with them, though it's annoying having Magic Weapon fall off when I swap weapons or OH, but it probably won't affect my farming all that much.

Yeah that part is annoying, not as annoying as corpse running because you blew yourself up on an RD pack in Archon though!

Thanks for the tips regarding CM build, i'm investing some time gearing it for around 20-30m.

:edit: wow, so 10m invested and have a decent CM set and am AMAZED at how good and resilient the build is.

Should my next upgrade be a weapon? Lately I've just been staring at memptos hoping one with crit will be posted for cheap, with no luck...

and every other slot an upgrade is either 1000mil+ or more of a side grade. I even have a pair of innas temperance, but at the cost of 5k dps...I like my survivability.

Guess my post is just asking which slot of mine is behind the most? (archon farming gear on atm) and is there any chance of getting a meaningful upgrade in the 100mil range?

Honestly, for 100M, I'm not certain you'll be able to get any meaningful upgrades. You're at the point where everything will probably be at least 300M and up. For 100M, you can probably nab a slightly better Vile Ward with slightly more DPS at the cost of a few hundred HP's worth of vitality, or a higher DPS Witching Hour without as much EHP.

If you can manage to find a pair of Inna's Temperance with vitality, you should still be in good shape EHP-wise for Archon farming. However, you will not likely be getting a 90+ int with decent vit Inna's for 100M. You're better off continuing your farm and continue selling things you find for quick gold. At paragon 50, you should be relatively decent drops if you're farming MP3+ with Archon. Grind out some more paragon for the MF bonuses. On average, I get about 1-2 unique items per Alkaizer run, which is essentially at least 6 uniques per hour. Chances are at least one of them will be worth 10M+ when running with over 425% MF on MP3, not to mention the pages and pages of rares that are gathered. This is just my average, but it's all dumb luck in the end.

Farm and be patient, or if you have the extra income to do so (as a last resort), you can treat yourself to $50 worth of gold or something. I'm at the point where I cannot by any means make an upgrade unless I farm for a month or two straight. I occasionally put some money in to cover whatever extra gold I need to buy out an upgrade. I don't recommend doing this unless you're at the level where upgrading anything significant at all is near impossible with grinding alone. Some people go out to the bar once a week and bust $80 on drinks. I might bust out $50 from my weekly paycheck to add some more gold to the bank.

Can't decide which slot I should upgrade next. I have 197k dps buffed in archon spec, still a lot of room for improvement, but I have no idea how I can get extra dps w/ loosing too much EHP.

Last week I also started to play as CM wizzard and killing ubers with my friends. Before that I was thinking about upgrading OH or right ring or even getting rid of my pants, now I'm unsure about what piece I should change to benefit both specs=/

PS Kinda offtopic, but where CM wizzards get loh/LS ? CM wizzards are bound to chantodo's will, which can't roll LS/socket (or crit dmg) at the same time.

Some good CM sources of LoH include Blackthorn pants, Blackthorn amulet, Storm Crow helm, or rare rings/amulet. I currently use the pants and helm from that list for 890 or so LoH and it works pretty well at my gear level.

Regarding Archon upgrades, dropping a little EHP could be ok, depending on how much you have. I'm using around 240k for MP2 and it works fine. For MP3 I'd recommend a bit more, like 260-270 since mob damage only increases by about 10% (1.2 to 1.31 damage modifier). I also only have 25.5k hp, so damage resistance of around 90% is what I'd try to shoot for, in Archon form of course (with whatever armor you normally use). Otherwise, I can't really recommend specific upgrades unless I see your Archon gear.